Characterization of <i>Riemerella anatipestifer</i> Strains Isolated from Various Poultry Species in Poland

• Main Authors: Anna Nowaczek (Author), Marta Dec (Author), Dagmara Stępień-Pyśniak (Author), Jarosław Wilczyński (Author), Renata Urban-Chmiel (Author)
• Format: Book
• Published: MDPI AG, 2023-11-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.3390/antibiotics12121648; 2079-6382
• Keywords: <i>Riemerella anatipestifer</i>; MALDI-TOF MS; phylogeny; MIC; poultry; 16S RNA; Therapeutics. Pharmacology; RM1-950
• Source: Antibiotics, Vol 12, Iss 12, p 1648 (2023)

<i>Riemerella anatipestifer</i> (<i>R. anatipestifer</i>) is one of the common pathogens found in poultry flocks, resulting in serious economic losses for the poultry industry due to high mortality, reduced growth rate, poor feed conversion, increased condemnations, and high treatment costs. The aim of this study was to phenotypically characterize phylogenetic relationships and assess the presence of resistance gene strains of <i>R. anatipestifer</i> obtained from various poultry species in Poland. A total of 57 isolates of <i>Riemerella</i> were included in this study. A polymerase chain reaction (PCR) and matrix assisted laser desorption ionization mass spectrometry (MALDI-TOF MS) were used for identification of the strains. The phylogenetic relationship of the <i>R. anatipestifer</i> isolates was determined by analysing the <i>rpo</i>B gene sequence. The susceptibility to antibiotics was evaluated by minimum inhibitory concentration (MIC) in liquid media. All of the field strains of <i>R. anatipestifer</i> were grouped into one of two clades resulting from <i>rpo</i>B gene sequencing. High MIC₅₀ and MIC₉₀ values were obtained for gentamycin, amikacin, and colistin. Low MIC₅₀ and MIC₉₀ values were obtained for amoxicillin cefuroxime, cefoperazone, piperacillin, and trimethoprim/sulfamethoxazole. Among the resistance genes, <i>tet(X)</i> and <i>ermF</i> were identified most frequently. This is the first phenotypic characterization of <i>R. anatipestifer</i> strains obtained from poultry flocks in Poland.